Sign up eccentric loner (5)

I believe the answer is:

enrol

'sign up' is the definition.
(I've seen this before)

'eccentric loner' is the wordplay.
'eccentric' indicates anagramming the letters.
'loner' anagrammed gives 'ENROL'.

(Other definitions for enrol that I've seen before include "Enlist" , "Register (as student)" , "Become a member" , "Loner inclined to join in" , "Recruit" .)

I've seen this clue in The Mirror.

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